The shooting took place around 6:30 p.m. in the 1000-block of West 79th Street outside a funeral home.
Police said a black Chevrolet Malibu was driving westbound on 79th when occupants inside began firing at the attendees of a funeral. People at the funeral returned gunfire.
The car turned and continued to fire before crashing about midway down the block, police said.
Police said 15 people, 10 women and five men, were taken to five different hospitals with gunshot wounds.
Mayor Lori Lightfoot and CPD Superintendent David Brown all pleaded with the public for anyone with information to come forward, and Father Michael Pfleger of St. Sabina church is offering a $15,000 reward; $1,000 for each of the people who were shot.
"This is a mourning morning, another day when we start with despair," Lightfoot said.
Seven of the women, whose ages range from 21 to 65, were transported to hospital in good condition.
Three women, ages 26, 43 and 46, were transported to hospitals in serious condition.
Three men, ages 31, 32 and 38, were hospitalized in serious condition and a 22-year-old man was hospitalized in good condition.
Police said the three in the Malibu, which had been reported stolen, fled in different directions after the crash. One person of interest is currently being interviewed, according to police.
Suburban police, professionals struggle with growing funeral violence
A security camera from a local business captured the violence and the moments of chaos that followed.
Family and friends were paying respects to a 31-year-old man who had been shot to death last week at 74th Street and Stewart Avenue. His twin sister was among those wounded.
"What makes this incident especially heinous, is that those shooters took advantage of families and friends who were gathered to mourn the death of a young man who himself had lost his life just the week before," Mayor Lightfoot said.
Donnie Weathersby, 31, was killed last week in a gang-related shooting in Englewood.
Police said rival gang members retaliated Tuesday night at the funeral home.
Tamar Manasseh, with Mothers/Men Against Senseless Killings, said she warned Chicago police that the gunfire was coming.
"I saw something, I said something," Manasseh said. "I put myself at risk. I put my family at risk, saying something and the police didn't act."
Supt. Brown said, "We had two police squad cars there and a full tac team in the area. We treat all of our funerals that have any gang rivalry or gang connections in similar ways."
Brown, trying to put some perspective on the challenge facing police, said the city has 117,000 gang members, 55 major gangs, 747 smaller factions and 2,500 subsets of those factions.
"In any day of the week, any hour of the day, there are several hundred gang conflicts related to that 117,000 gang members," he said.
"I recognize that there is fear, and we understand that, but if we are silent the violence will continue," Mayor Lightfoot said.
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The mayor also hit back against President Trump in a Wednesday afternoon press conference, after the president directly referenced the funeral shooting in a news conference announcing a new "law-and-order" initiative that will send hundreds of federal agents to Chicago.
"The president is trying to divert attention from his failed leadership on COVID-19," she said. "If the president really wanted to do something to aid cities, as I wrote in a letter to him on Monday to which he has not responded, if he really wanted to help us, there are some things that the federal government is uniquely qualified to do."
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Some activists said police were warned about a potential shooting at the funeral. Police said they did have some intelligence, so they had two squad cars at the funeral home and a tactical team in the area, but it didn't prevent the shooting.
Mayor Lightfoot said the shooters took advantage of grieving families. At a press conference Wednesday morning, she addressed those responsible for the shooting.
"Picking up a gun...that solves nothing but causes so much lifelong pain. I pray for you but I also pray that we find you and that we bring you to justice," Mayor Lightfoot said.
Mayor Lightfoot addresses shooters: "Picking up a gun...that solves nothing"
NEIGHBORS SHAKEN BY GANG-RELATED MASS SHOOTING
The level of violence unleashed has shaken some residents in a whole new way.
"We thought it was a war out here," said witness Arnita Geder. "It's ridiculous over here. All this shooting that is going on around here. It really needs to stop in this area."
"We was just hearing a lot of gunshots and a lot of people screaming, trying to run for cover, trying to get so they won't get shot," said Sheila Harris, resident.
Harris and her 5-year-old son were inside their apartment when they heard the shots, and immediately dropped to the floor to take cover.
"It was, like, so terrifying that I called my husband and I told my son to stay down. Don't move," she said.
"As the people were coming out of the funeral home, the shots rang out like they were literally raining on them," said witness Jenneth Hughes.
A day later, some residents are still on edge.
"We just got to keep praying," said Auburn Gresham resident Major Harris. "All the community has got to bond together. That's the only way we're going to stop all this gun violence."
Local Pastor Marvin Hunter came to the corner to pray for peace as he welcomes federal help to deal with the neighborhood violence.
"I think it is a good thing. We need all the hands on deck. I believe this is an American problem so all of America needs to join in and help us to solve the problem," said Pastor Hunter.
Police said they counted 60 shell casings at the scene.
Anyone with information is asked to contact Area 2 detectives at (312) 747-8271 and anonymous tips can be sent to CPDtip.com.
Latest funeral attack as authorities grapple with growing memorial violence